CVE-2021-22951 — concrete5/core
HIGHCVE-2021-22951 is a high-severity (CVSS 7.5) CWE-639 vulnerability in concrete5/core. A fix is available for concrete5/core — see the affected versions and patch details below.
Password exposure in concrete5/core
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2021-22951 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
concrete5/coreReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Packagist packages — download data is not available via public APIs for these ecosystems.
Description
Unauthorized individuals could view password protected files using view_inline in Concrete CMS (previously concrete 5) prior to version 8.5.7. Concrete CMS now checks to see if a file has a password in view_inline and, if it does, the file is not rendered.For version 8.5.6, the following mitigations were put in place a. restricting file types for view_inline to images only b. putting a warning in the file manager to advise users.Credit for discovery: "Solar Security Research Team"Concrete CMS security team CVSS scoring is 5.3: AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:NThis fix is also in Concrete version 9.0.0
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐘Packagist | concrete5/core | all versions | 8.5.7composer require concrete5/core:^8.5.7 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for concrete5/core, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update concrete5/core to 8.5.7 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-22951 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2021-22951 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2021-22951. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2021-22951 in your dependencies?
O3 Security finds CVE-2021-22951 across Packagist dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.